Extended Data Fig. 6: Identifying the potential calcium (Ca²⁺) binding site in DGC’s CDHL domains.

a, Superposition of the CDHL domains with focused views of the Ca²⁺ coordination site in endo-fucoidan hydrolase MfFcnA4 (PDB ID: 6DLH, purple), and potential Ca²⁺ binding sites in dystroglycans (salmon and grey) and α-sarcoglycan (cyan). Residues possibly involved in Ca²⁺ coordination are annotated. b, Cross-species multiple sequence alignment of the three CDHL domains in DGC. Red background depicts identical residues in all CDHL domains. Conserved residues are coloured in red and divergent residues are in black. All potential coordination residues shown in a are labelled with red circles. MfFcnA4 residues structurally homologous to CDHL2 positions are numbered; green-filled dash circles (half: not conserved; full: identical) indicate potential Ca²⁺ binding sites in CDHL2.